<template>
    <el-breadcrumb class="app-breadcrumb" separator="/">
        <transition-group name="breadcrumb">
            <el-breadcrumb-item v-for="(item, index) in levelList" :key="item.path">
                <span v-if="item.redirect === 'noRedirect' || index == levelList.length -1 " class="no-redirect">{{ item.meta.title }}</span>
                <a v-else @click.prevent="handleLink(item)">{{ item.meta.title }}</a>
            </el-breadcrumb-item>
        </transition-group>
    </el-breadcrumb>
</template>

<script>

export default{
    data() {
        return {
            levelList: null
        }
    },

    watch:{
        $route(route){
            if(route.path.startsWith('/redirect/')){
                return ;
            }
            
            this.getBreadcrumb()  
        }
        
    },

    created() {
        this.getBreadcrumb();
    },

    methods: {
        getBreadcrumb(){
            let matched = this.$route.matched.filter(item => item.meta && item.meta.title)
            const first = matched[0]

            if(!this.isDashboard(first)){
                matched = [{path: '/index', meta:{title:'首页'}}].concat(matched)
            }

            this.levelList = matched.filter(item => item.meta && item.meta.title && item.meta.breadcrumb !== false)
        },

        isDashboard(route){
            const name = route && route.name
            if(!name){
                return false;
            }
            return name.trim() === 'Index'
        },

        handleLink(item){
            const {redirect, path} = item
            if(redirect){
                this.$router.push(redirect)
                return ;
            }
            this.$router.push(path)
        }
    },
}


</script>

<style lang="scss" scoped>
.app-breadcrumb.el-breadcrumb{
    display: inline-block;
    font-size: 14px;
    line-height: 50px;
    margin-left: 8px;

    .no-redirect {
        color: #97a8be;
        cursor: text;
    }
}

</style>